Physical Properties of Restorative Materials and Clinical Studies

Dr. Karen Schulze

In a recent clinical study, we evaluated the success rate of MTA (mineral trioxide aggregate cement) placement as pulp cup procedure after a pulp exposure in sound dentin.

Our laboratory research is focused on the in vitro evaluation of shear bond strength between different materials. It is common to use dental hard tissues like human dentin or enamel in combination with dental products like bonding materials and composites. Our goal is to evaluate the adhesion of those interfaces crucial to everyday dental practice by using a universal testing machine for shear bond tests.

Other interfaces can be tested as well. Currently we have a study in progress in which we test the shear bond strength between stainless steal crowns and flowable composites. The main purpose is to find out if flowable composite can be used to veneer anterior stainless steel crowns for use in pediatric dentistry.

Another project is evaluating the strength of the interface between glass-ionomer cements and composites. The use of these two materials in the clinic is the so-called “sandwich technique” for treating Class V lesions.

We are also investigating physical properties of new ceramic materials such as zirconia, which have been introduced to dentistry during the last decade, and have become increasingly popular. In fact, our school was among the pioneers in introducing zirconia custom-made posts and cores for restorative dentistry in this country. Our lab is currently evaluating the fracture mechanics of various zirconia posts and cores.